Label Distribution Protocol (LDP) defines mechanisms for setting up Point-to-Point (P2P) and Multipoint-to-Point (MP2P) Label Switched Paths (LSPs) in a network. The set of LDP extensions for setting up P2MP or MP2MP LSPs may be referred to as multipoint LDP (mLDP), which may be specified in Internet Engineering Task Force (IETF) Request for Comments (RFC) 6388, titled “Label Distribution Protocol Extensions for Point-to-Multipoint and Multipoint-to-Multipoint Label Switched Paths,” which is hereby incorporated by reference.
Service providers continue to deploy real-time multicast applications using mLDP across Multiprotocol Label Switching (MPLS) networks. There is a clear need to protect these real-time applications and to provide the shortest switching times in the event of failure. Protecting services may include the establishment of backup paths for link or node failure. Under such practices, traffic should transmit across the backup path once a failure has been detected on the primary path. Current solutions suffer several known problems, particularly with respect to efficiently timing the establishment and disestablishment of backup paths. A rapidly established backup path is preferable for data continuity. If the backup path is disestablished too quickly, the receiver experiences packet loss; if too slowly, package duplication results.